An interferon- and ribavirin-free regimen of sofosbuvir/ledipasvir (Harvoni) taken for just 6 weeks was enough to cure HIV-positive people with recent hepatitis C virus (HCV) infection if their HCV viral load was low, but those with high HCV levels may need longer treatment, according to study findings presented at the Conference on Retroviruses and Opportunistic Infections (CROI 2016)this week in Boston. Presenter Jürgen Rockstroh of the University of Bonn predicted that HCV viral load will become a key factor when making decisions about treating acute hepatitis C.

Studies done in the interferon era showed that treating people during the acute stage of HCV infection led to much higher response rates and required a shorter duration than interferon-based therapy started during chronic infection.

The advent of direct-acting antivirals (DAAs) in interferon-free regimens has made chronic hepatitis C treatment shorter, better tolerated, and more effective, and many experts expected the same would be true for acute HCV infection. But a combination of sofosbuvir plus ribavirin taken for 12 weeks produced a sustained response rate of only 59% in a small study of HIV-positive men with acute hepatitis C presented at the recent 2015 AASLD Liver Meeting.

There are currently no specific direct-acting antiviral regimens approved for the treatment of acute HCV infection. Current guidelines recommend using the same DAA options as for chronic infection, or even continuing to use interferon and ribavirin.

Rockstroh and colleagues conducted a study to evaluate the safety and efficacy of short-duration treatment using the HCV NS5B polymerase inhibitor sofosbuvir and the NS5A inhibitor ledipasvir for HIV-positive people with genotype 1 or 4 acute hepatitis C.

The analysis included 26 HIV-positive participants at 5 sites in Germany and the U.K. All were men, most were white, and the mean age was 41 years. They had acute HCV infection, defined as a positive HCV RNA test following a negative HCV antibody or RNA test within the past 6 months, or elevated ALT/AST during the past 6 months with no other known cause. About two-thirds had HCV genotype 1a and the rest genotype 4; the mean HCV viral load at baseline was 5.4 log IU/mL.

Participants could either be on antiretroviral therapy (ART) with suppressed HIV viral load or not on ART with no plans to start. Treated patients were using a variety of antiretrovirals that can be co-administered with sofosbuvir/ledipasvir. The most common regimens were efavirenz (Sustiva), raltegravir (Isentress), dolutegravir (Tivicay), or boosted atazanavir (Reyataz) plus tenofovir/emtricitabine (the drugs in Truvada).

All participants in this open-label study received sofosbuvir/ledipasvir in a fixed-dose coformulation for 6 weeks.

No new NS5A or NS5B resistance-associated viral variants were detected at the time of relapse.

Treatment was generally safe and well-tolerated with 1 unrelated serious adverse event and no treatment discontinuations for this reason.

The most common adverse events were fatigue (7%), nasopharyngitis (7%), and headache 6%), mostly mild or moderate.

Safety profiles were similar for patients receiving boosted or unboosted tenofovir-based ART regimens.

Given that there were no relapses among participants with baseline HCV RNA <6.9 log IU/mL, the researchers concluded, "acutely HCV-infected patients with a higher viral load should be considered for longer duration of therapy."

Rockstroh noted that although shorter interferon-based treatment works well for acutely infected patients, "unfortunately DAAs don't behave the same way."

He acknowledged that it is still not clear when is the best time to treat people with acute HCV infection. About 25% of all people and 15% of HIV-HCV coinfected people with acute infection will spontaneously clear the virus. Many experts recommend waiting to see if treatment is really needed, but the likelihood of transmitting HCV during this early period can be high.

When considering guidelines for acute hepatitis C treatment, "everything is going to be driven by viral load," Rockstroh predicted.

Researchers have seen no decline in new hepatitis C virus (HCV) infections among HIV-positive men who have sex with men in 16 European CASCADE cohorts, according to a poster presented at the 15th European AIDS Conference last week in Barcelona. However, trends seem to differ between various regions of Europe.

The cost of treating hepatitis C is likely to decline dramatically over the next decade in the U.S., not because of cuts in drug prices, but because the population in need of treatment will shrink by 2020 as a majority of patients will already have been treated, according to research by Jagpreet Chhatwal of Massachusetts General Hospital and colleagues presented at the AASLD Liver Meeting in San Francisco last month.

Hepatitis C treatment that leads to sustained virological response (SVR) -- generally regarded as a cure -- was associated with a reduced risk of liver-related death and improved overall survival in an analysis of 3500 HIV and hepatitis C virus (HCV) coinfected patients, according to a presentation at the 15th European AIDS Conference last week in Barcelona. A related study found that while some liver-related events are declining over time, liver cancer remains a risk for coinfected people.

Merck's grazoprevir/elbasvir combination cured 93% of people with HIV and hepatitis C coinfection, was well-tolerated, and did not appear to interact with antiretrovirals, according to final results from the C-EDGE Co-infection study presented at the 2015 AASLD Liver Meeting last month in San Francisco. These results confirm that HIV/HCV coinfected people respond as well to interferon-free therapy as those with HCV alone.

Most hepatitis C patients in the GECCO German hepatitis C cohort who were treated with sofosbuvir/ledipasvir (Harvoni) for 8 weeks in a real-world clinical setting achieved sustained virological response, even those who are advised to stay on treatment for 12 weeks due to factors such as liver cirrhosis, prior treatment experience, and high HCV viral load, according to a presentation last week at the 15th European AIDS Conference in Barcelona.